While dust storms on Mars are hazardous, the electric discharge from these events could be playing a role in the red planet's chlorine cycle.
Dust Storms on Mars
There are pertinent dangers that dust storms on Mars bring. While smaller ones regularly take place, bigger ones may happen annually. Science Alert reports that these big ones could even spend weeks covering areas as big as continents.
Every three years on Mars (which is roughly equivalent to five and a half years on earth), storms can be big enough to engulf the whole red planet. These may even last for two months.
Such dust storms serve a vital role in the various processes that shape the Martian surface and that can be seen from earth at times. When storms become strong, dust grains become electrified because of the friction between them. In such a case, negative and positive charges are transferred via static charges. Unlike that of earth, such discharges do not look like lightning flashes.
Recent research has revealed that these electrical charges may be a key driver for the red planet's chlorine cycle.
The Role of Electrical Discharges from Dust Storms in Mars' Chlorine Cycle
The study was included in the Geophysical Research Letters publication. As part of the study, the researchers demonstrated how storm-caused electrical discharges may be the culprit behind chloride salt decomposition, atmospheric chlorine creation, and other compounds of chemicals within the Martian surface.
According to Universe Today, chlorine is considered a mobile element, among four others, on the Martian surface. Similar to the water cycle of the earth, it means that chlorine transfers from the surface into the atmosphere in varying forms. In the atmosphere, it exists as a gas. On the surface, deposits of chlorine can be spotted. Such deposits are similar to the pans of salt that can be spotted throughout the earth.
Like those on earth, chloride deposits on the Martian surface are likely dried remnants of briny water patches that existed atop the surface. Universe Today reports that it is theorized that these resulted from interactions between the atmosphere and surface during Amazonian times.
Because the exchange between the two no longer takes place, scientists have been thinking about the link between these chloride deposits and atmospheric chlorine. This is where the electrical discharges come into play, as they are efficient in facilitating the exchanges between the atmosphere and the surface.
Universe Today reports that the possibility of dust storms being a reactive chemistry source on the red planet was first brought up during the Viking 1 and 2 missions in the 1970s. However, it was difficult to dig deeper since the Schiaparelli lander of the ESA crashed into the surface. Consequently, scientists needed to adhere to experimental research and climate modeling.
The findings revealed that when electrostatic discharges interacted with chlorine salts in an environment that was rich in carbon dioxide, gaseous chlorine was released. Carbonates and perchlorates could also be generated.
However, it was in this study that planetary scientists first tried to quantify the chemicals produced during dust storms. They did so by conducting various experiments at the PEACh (Planetary Environment and Analysis Chamber) of Washington University.
Findings confirmed their assumptions. Alien Wang, the research leader from Washington University, says that Mars' thin atmosphere makes breaking down of electrical fields into discharge easier. It is a hundred times easier compared to that of earth.
Moreover, the rate of reaction was dramatic. In an electrostatic discharge experiment that lasted seven hours, the researchers discovered that at least one out of a hundred molecules of chlorine decomposed and expelled an atom of chlorine.
On top of this, electrical discharge also accounted for heightened carbonate and perchlorate concentrations on the red planet's topsoil. The high yields also accounted for high hydrogen chloride observations that were seen during dust storms in 2018 and 2019.
Findings show that the activities of Martian dust could indeed be a driver of the red planet's chlorine cycle.
Check out more news and information on Space in Science Times.
